Expectations and Assessments in Research

In a randomized controlled trial, individuals with MS who played a research version of the Posit Science brain training game “Brain HQ” improved 29% on neuropsychological tests, compared to 15% improvement in the control group who played “ordinary video games.” Both groups received weekly coaching sessions. The “placebo group” was actually more compliant in the study, playing on average 19 hours more than their study counterparts. I’m curious why the researchers called the control group a “placebo” group, which assumes any effects are essentially psychological. Given that playing some “ordinary” video games have been associated with cortical changes, what is the basis of this assumption? I also want to know more about the expectations of study participants. Did these expectations differ depending on study condition? I suspect the reason the controls played their games a lot more was they were having more fun. If one condition was more effortful and less fun than the other, would the groups differ in any systematic way in their expectations of cognitive change or in how they approach the post-training assessment tests?

I was recently involved in a study involving game-assisted cognitive training and remember a participant who cancelled a post-training assessment because he hadn’t gotten much sleep and didn’t want to take the tests when tired. Would he have still cancelled if he had no hope or expectation of improvement? When you invest a lot of time and effort in something, you want something to show for it. It doesn’t matter that participants aren’t informed of testing results; some participants will probably still be motivated to do better. But if participation is all fun and little work, would a participant be as motivated to do as well as possible on the post-tests?

There are plenty of papers about the connection between expectations, personal investment and tests scores in academic contexts – but I couldn’t find any on the role of these factors on assessments in research. Please, someone, do a study!

References:

NYU Langone Medical Center / New York University School of Medicine. "At-home cognitive remediation may help cognitive symptoms in multiple sclerosis." ScienceDaily. ScienceDaily, 16 April 2016. <www.sciencedaily.com/releases/2016/04/160416094758.htm>.